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2=2xx+x\left(-3\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
2=2x^{2}+x\left(-3\right)
Multiply x and x to get x^{2}.
2x^{2}+x\left(-3\right)=2
Swap sides so that all variable terms are on the left hand side.
2x^{2}+x\left(-3\right)-2=0
Subtract 2 from both sides.
2x^{2}-3x-2=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-\left(-3\right)±\sqrt{\left(-3\right)^{2}-4\times 2\left(-2\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -3 for b, and -2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\times 2\left(-2\right)}}{2\times 2}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9-8\left(-2\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-3\right)±\sqrt{9+16}}{2\times 2}
Multiply -8 times -2.
x=\frac{-\left(-3\right)±\sqrt{25}}{2\times 2}
Add 9 to 16.
x=\frac{-\left(-3\right)±5}{2\times 2}
Take the square root of 25.
x=\frac{3±5}{2\times 2}
The opposite of -3 is 3.
x=\frac{3±5}{4}
Multiply 2 times 2.
x=\frac{8}{4}
Now solve the equation x=\frac{3±5}{4} when ± is plus. Add 3 to 5.
x=2
Divide 8 by 4.
x=-\frac{2}{4}
Now solve the equation x=\frac{3±5}{4} when ± is minus. Subtract 5 from 3.
x=-\frac{1}{2}
Reduce the fraction \frac{-2}{4} to lowest terms by extracting and canceling out 2.
x=2 x=-\frac{1}{2}
The equation is now solved.
2=2xx+x\left(-3\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
2=2x^{2}+x\left(-3\right)
Multiply x and x to get x^{2}.
2x^{2}+x\left(-3\right)=2
Swap sides so that all variable terms are on the left hand side.
2x^{2}-3x=2
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{2x^{2}-3x}{2}=\frac{2}{2}
Divide both sides by 2.
x^{2}-\frac{3}{2}x=\frac{2}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-\frac{3}{2}x=1
Divide 2 by 2.
x^{2}-\frac{3}{2}x+\left(-\frac{3}{4}\right)^{2}=1+\left(-\frac{3}{4}\right)^{2}
Divide -\frac{3}{2}, the coefficient of the x term, by 2 to get -\frac{3}{4}. Then add the square of -\frac{3}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{3}{2}x+\frac{9}{16}=1+\frac{9}{16}
Square -\frac{3}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{3}{2}x+\frac{9}{16}=\frac{25}{16}
Add 1 to \frac{9}{16}.
\left(x-\frac{3}{4}\right)^{2}=\frac{25}{16}
Factor x^{2}-\frac{3}{2}x+\frac{9}{16}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-\frac{3}{4}\right)^{2}}=\sqrt{\frac{25}{16}}
Take the square root of both sides of the equation.
x-\frac{3}{4}=\frac{5}{4} x-\frac{3}{4}=-\frac{5}{4}
Simplify.
x=2 x=-\frac{1}{2}
Add \frac{3}{4} to both sides of the equation.